View Administrator a/c At welcome Screen

Now head up to HKEY_LOCAL_MACHINE\Software\Microsoft\WindowsNT\CurrentVersion\Winlogon\SpecialAccounts\Userlist

create a new DWORD entry and name it as Administrator and change its value to 1.

exit and reboot for the changes to take effect.
To change it back change its value to 0 or simply delete the key.